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251.
According to Food and Agriculture Organization and Intergovernmental Panel on Climate Change reports, climate change will lead to a severe food-supply problem. In the future, food production will continually decrease because of aggravated effects of climate change, causing food production to continually decrease. Food production will be unable to satisfy the demand of the global population, leading to a food-security crisis. As the world population continues to increase, the shortage of food will become increasingly severe, particularly for those located in “climate impact hotspots” of tropical, subtropical, small-island countries, and countries that are dependent on imports to meet domestic demand such as Taiwan. Numerous Taiwanese studies have suggested that agricultural and fishery productivity has declined because of climate variation, which may cause changes and instability in food quantity and quality, and increase deficiency and uncertainty in the food supply. Therefore, to discuss the risks posed by climate change to the stability of food supply and demand, this paper, taking Taiwan as a case, explored the impact of climate variation on food security and future adaptation strategies. TaiCCAT’s supportive system for decision-making (TSSDA) was adopted here to assess and analyze the current situations of agricultural and fisheries production and supply, as well as future food supply risks, in addition to evaluating the deficiencies in the existing climate adaptation strategies in order to plan and revise feasible future adaptation alternatives. Based on the rule of risk management, the adaptation strategies recommended in this study were differentiated into two categories: proactive adaptation and planned adaptation. Proactive adaptation is emphasized to counter the uncertainty of food production, which increases the difficulty of production and necessity to import food. Conversely, planned adaptation can be used to manage the uncertainty of food supply to implement adjustments in production and marketing, as well as to mitigate the impact of climate variation.  相似文献   
252.
基于高斯烟团模型建立了适合新场气田的输气管道泄漏模型,考虑了管道压力、泄漏衰减、环境因素的影响,模拟分析了管道压力、泄漏时间与大气稳定度对泄漏天然气燃爆区域的影响,并计算获得了新场气田某干线天然气泄漏下风向燃爆极限距离图版,对指导管道安全政策、方案制定具有重要意义。  相似文献   
253.
根据广东省滨海电厂的类型和污染特点,建立了针对滨海的燃煤电厂、核电厂、LNG电厂的环境成本估算体系,通过采用环境价值标准法、机会成本法、污染损失系数法、模型公式等多种评估方法,估算得出广东省各类型滨海电厂环境成本为:核电0.0341元/kWh,煤电0.03109元/kWh,LNG电厂0.010386元/kWh.结合各类型发电技术的一般成本,得出在综合考虑环境友好性及经济性的情况下,广东省滨海电厂最优的发展选择为核电,其次为煤电,LNG电厂暂时不宜过多地发展.  相似文献   
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Introduction. Navigated safety inspection based on task-specific checklists can increase the hazard detection rate, theoretically with interference from scene complexity. Visual clutter, a proxy of scene complexity, can theoretically impair visual search performance, but its impact on the effect of safety inspection performance remains to be explored for the optimization of navigated inspection. This research aims to explore whether the relationship between working memory and hazard detection rate is moderated by visual clutter. Methods. Based on a perceptive model of hazard detection, we: (a) developed a mathematical influence model for construction hazard detection; (b) designed an experiment to observe the performance of hazard detection rate with adjusted working memory under different levels of visual clutter, while using an eye-tracking device to observe participants’ visual search processes; (c) utilized logistic regression to analyze the developed model under various visual clutter. Conclusion. The effect of a strengthened working memory on the detection rate through increased search efficiency is more apparent in high visual clutter. This study confirms the role of visual clutter in construction-navigated inspections, thus serving as a foundation for the optimization of inspection planning.  相似文献   
257.
Environmental Science and Pollution Research - To investigate the relationship between health effect profile and co-exposure to heavy metal, 254 sanitation workers from Guangzhou, China, were...  相似文献   
258.
煤—焦炉气共热解脱硫脱氮的研究   总被引:3,自引:0,他引:3  
廖洪强  李保庆 《环境化学》1998,17(4):332-338
本文对兖州高硫煤在不同压力、升温速率及终态温度条件下,与焦炉煤气在10g固定床反应器中共热解所得半焦无元素组成进行系统的分析比较,结果表明,在压力为3MPa温度为650℃,升温速率为5℃、min^-1较为温和的条件下,兖州高硫煤与焦炉气共热解的脱硫脱氮率分别高达86.47%和59.63%,硫在热解产品中的分布大致为:半焦中70%,焦油中10%,气相中20%;氮的分布为:60-70%滞留的半焦中,2  相似文献   
259.
Abstract

A process on crystallized precipitation of ammonium by adding magnesium salt and phosphate was carried out to improve C/N ratio in swine wastewater. After completion of crystallized precipitation of ammonium, an intermittent aeration process with aeration and non‐aeration periods alternated at interval of 1:1 hr day‐1 is used for the improved swine wastewater (T‐N/BOD=0.14: BOD=8200 mg/liter and T‐N=1166 mg/liter). The results obtained from the experiment show that the removal ratios of T‐N and NH4‐N are 91% and 99%, respectively. T‐P is not removed, while the removal ratio of PO4‐P is 60% as 3% of CaCl2 liquid is added. The results also indicate that dilution with water is effective to improve the removal of phosphorus even if raw swine wastewater contains high concentrations of T‐N, T‐P, BOD, and TOC.  相似文献   
260.
This study aimed to understand the soil fauna characteristics during the litter decomposition process of perennial herb Deyeuxia arundinacea. The litters were put in 6-, 30-, and 260-mesh litterbags to investigate their mass loss and the dynamics of soil faunal community during Aug. 2013 to Jul. 2014. Faster decomposition rate of Deyeuxia arundinacea in different meshes was found in the early period than in mid- and end-periods. Among different mesh sizes, 6-mesh had the fastest decomposition rate, followed by 30-mesh and 260-mesh. A total of 2218 individuals of soil fauna were obtained in different meshes, with 958, 737 and 523 individuals in 30-, 260- and 6-mesh respectively. Oribatida and Poduridae were the dominant groups, accounting for 73.22% of total individuals. The soil animal individual and group densities shared a very similar trend among the decomposition bags of three aperture sizes, all with obvious characteristics of seasonal dynamic distribution. During the 12 months of decomposition, the density of soil animal groups did not show significant difference between the 6 mesh and 260 mesh decomposition bags except for May. Correlation analysis showed that the group density was highly significantly correlated with average monthly temperature and rainfall, and the individual density significantly correlated with the average monthly temperature. The results indicated that the structure and diversity of soil fauna community of Deyeuxia arundinacea are influenced by hydrothermal conditions. The findings help in understanding the effect of soil fauna to perennial herb litter decomposition.  相似文献   
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